feat: Flyweight

README.md

@@ -28,7 +28,7 @@ This project demonstrates various design patterns implemented in C#. Design patt
    - [ ] Composite
    - [ ] Decorator
    - [ ] Facade
-   - [ ] Flyweight
+   - [X] Flyweight
    - [ ] Proxy
 
 3. **Behavioral Patterns**

src/Creational/AbstractFactory/AbstractFactory.cs

@@ -2,6 +2,7 @@
 using DesignPatterns.Creational.AbstractFactory.PolicyTypes.Car;
 using DesignPatterns.Creational.AbstractFactory.PolicyTypes.Health;
 using DesignPatterns.Creational.AbstractFactory.PolicyTypes.Home;
+using DesignPatterns.Creational.FactoryMethod;
 using DesignPatterns.Utils.Display;
 
 namespace DesignPatterns.Creational.AbstractFactory;

src/Creational/Builder/Builder.cs

@@ -1,4 +1,5 @@
-using DesignPatterns.Utils.Display;
+using DesignPatterns.Creational.FactoryMethod;
+using DesignPatterns.Utils.Display;
 
 namespace DesignPatterns.Creational.Builder;
 
@@ -51,7 +52,7 @@ public void Run(string policyType)
         //5. **Learning Curve**:
         //   - For developers unfamiliar with design patterns, understanding and implementing the Builder pattern might require a learning curve, adding to the initial development time.
 
-        //### When to Use the Builder Pattern
+        //### When to Use the Builder IPattern
 
         //- **Complex Construction Logic**: When the construction of an object involves many steps, and the object has many configurations.
         //- **Immutability**: When you need to create immutable objects and want to provide a clear and concise way to construct them.

src/Creational/FactoryMethod/FactoryMethod.cs

@@ -3,7 +3,7 @@
 
 namespace DesignPatterns.Creational.FactoryMethod;
 
-public class FactoryMethod
+public class FactoryMethod 
 {
     private readonly IOutput _output;
 

src/Creational/Prototype/Prototype.cs

@@ -1,10 +1,8 @@
-
-using DesignPatterns.Creational.Builder;
-using DesignPatterns.Utils.Display;
+using DesignPatterns.Utils.Display;
 
 namespace DesignPatterns.Creational.Prototype;
 
-public class Prototype
+public class Prototype 
 {
     private readonly IOutput _output;
 
@@ -13,7 +11,7 @@ public Prototype(IOutput output)
         _output = output;
     }
 
-    public void Run()
+    public void Run(string policyType)
     {
 
         var originalPolicy = new InsurancePolicy()

src/Creational/Singleton/Singleton.cs

@@ -1,4 +1,5 @@
-using DesignPatterns.Utils.Display;
+using DesignPatterns.Creational.FactoryMethod;
+using DesignPatterns.Utils.Display;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -16,7 +17,7 @@ public Singleton(IOutput output)
             _output = output;
         }
 
-        public void Run()
+        public void Run(string policyType)
         {
             // Access the singleton instance
             InsurancePolicySingleton policy1 = InsurancePolicySingleton.Instance;

src/DesignPatterns.Adapter/Adapter/Adapter.cs

@@ -7,7 +7,7 @@
 
 namespace DesignPatterns.Structural.Adapter
 {
-    public class Adapter
+    public class Adapter 
     {
         private readonly IOutput _output;
 

src/DesignPatterns.Adapter/Bridge/Bridge.cs

@@ -3,7 +3,7 @@
 
 namespace DesignPatterns.Structural.Bridge
 {
-    public class Bridge
+    public class Bridge 
     {
         private readonly IOutput _output;
 

src/DesignPatterns.Adapter/Flyweight/Flyweight.cs

@@ -0,0 +1,35 @@
+using DesignPatterns.Utils.Display;
+
+namespace DesignPatterns.Structural.Flyweight
+{
+    public class Flyweight
+    {
+        private readonly IOutput _output;
+
+        public Flyweight(IOutput output)
+        {
+            _output = output;
+        }
+
+        public void Run()
+        {
+            var factory = new InsuranceTypeFactory();
+
+            // Shared insurance types
+            var healthType = factory.GetInsuranceType("Health", "Full Coverage");
+            var carType = factory.GetInsuranceType("Car", "Collision Coverage");
+
+            // Policies that share insurance types
+            var policy1 = new InsurancePolicy(healthType, "Mdu Doe", "P123456");
+            var policy2 = new InsurancePolicy(healthType, "Trev Doe", "P123457");
+            var policy3 = new InsurancePolicy(carType, "Dane", "P123458");
+            var policy4 = new InsurancePolicy(carType, "Menzi", "P123459");
+
+            // Display policy details
+            _output.Display(policy1.GetPolicyDetails());
+            _output.Display(policy2.GetPolicyDetails());
+            _output.Display(policy3.GetPolicyDetails());
+            _output.Display(policy4.GetPolicyDetails());
+        }
+    }
+}

src/DesignPatterns.Adapter/Flyweight/InsurancePolicy.cs

@@ -0,0 +1,21 @@
+namespace DesignPatterns.Structural.Flyweight;
+
+//Extrinsic State: This represents the unique state
+public class InsurancePolicy
+{
+    private readonly InsuranceType _insuranceType;
+    public string CustomerName { get; }
+    public string PolicyNumber { get; }
+
+    public InsurancePolicy(InsuranceType insuranceType, string customerName, string policyNumber)
+    {
+        _insuranceType = insuranceType;
+        CustomerName = customerName;
+        PolicyNumber = policyNumber;
+    }
+
+    public string GetPolicyDetails()
+    {
+        return $"Policy No: {PolicyNumber}, Customer: {CustomerName}, {_insuranceType.GetPolicyTypeDetails()}";
+    }
+}

src/DesignPatterns.Adapter/Flyweight/InsuranceType.cs

@@ -0,0 +1,19 @@
+namespace DesignPatterns.Structural.Flyweight;
+
+//Intrinsic State: This represents the shared state
+public class InsuranceType
+{
+    public string Type { get; }
+    public string Coverage { get; }
+
+    public InsuranceType(string type, string coverage)
+    {
+        Type = type;
+        Coverage = coverage;
+    }
+
+    public string GetPolicyTypeDetails()
+    {
+        return $"Type: {Type}, Coverage: {Coverage}";
+    }
+}

src/DesignPatterns.Adapter/Flyweight/InsuranceTypeFactory.cs

@@ -0,0 +1,18 @@
+namespace DesignPatterns.Structural.Flyweight;
+
+public class InsuranceTypeFactory
+{
+    private readonly Dictionary<string, InsuranceType> _insuranceTypes = new Dictionary<string, InsuranceType>();
+
+    public InsuranceType GetInsuranceType(string type, string coverage)
+    {
+        var key = $"{type}_{coverage}";
+
+        if (!_insuranceTypes.ContainsKey(key))
+        {
+            _insuranceTypes[key] = new InsuranceType(type, coverage);
+        }
+
+        return _insuranceTypes[key];
+    }
+}

src/DesignPatterns.Structural.Tests/FlyweightPatternTests.cs

@@ -0,0 +1,60 @@
+using DesignPatterns.Structural.Flyweight;
+using FluentAssertions;
+
+namespace DesignPatterns.Structural.Tests;
+
+public class FlyweightPatternTests
+{
+    public class InsuranceTypeFactoryTests
+    {
+        [Test]
+        public void ShouldReuseInsuranceTypeForSamePolicyType()
+        {
+            // Arrange
+            var factory = new InsuranceTypeFactory();
+
+            // Act
+            var type1 = factory.GetInsuranceType("Health", "Full Coverage");
+            var type2 = factory.GetInsuranceType("Health", "Full Coverage");
+
+            // Assert
+            type1.Should().BeSameAs(type2, "Factory should return the same instance for the same insurance type");
+        }
+
+        [Test]
+        public void ShouldCreateDifferentInsuranceTypesForDifferentPolicyTypes()
+        {
+            // Arrange
+            var factory = new InsuranceTypeFactory();
+
+            // Act
+            var healthType = factory.GetInsuranceType("Health", "Full Coverage");
+            var carType = factory.GetInsuranceType("Car", "Collision Coverage");
+
+            // Assert
+            healthType.Should().NotBeSameAs(carType, "Factory should return different instances for different insurance types");
+        }
+    }
+
+    public class InsurancePolicyTests
+    {
+        [Test]
+        public void ShouldStoreCustomerSpecificPolicyDetails()
+        {
+            // Arrange
+            var factory = new InsuranceTypeFactory();
+            var healthType = factory.GetInsuranceType("Health", "Full Coverage");
+
+            var policy1 = new InsurancePolicy(healthType, "Mdu Doe", "P123456");
+            var policy2 = new InsurancePolicy(healthType, "Trev Doe", "P123457");
+
+            // Act
+            var details1 = policy1.GetPolicyDetails();
+            var details2 = policy2.GetPolicyDetails();
+
+            // Assert
+            details1.Should().Be("Policy No: P123456, Customer: Mdu Doe, Type: Health, Coverage: Full Coverage");
+            details2.Should().Be("Policy No: P123457, Customer: Trev Doe, Type: Health, Coverage: Full Coverage");
+        }
+    }
+}

src/DesignPatterns.Structural.Tests/InsurancePolicyBridgeTests.cs

@@ -4,7 +4,7 @@
 
 namespace DesignPatterns.Structural.Tests;
 
-public class InsurancePolicyTests
+public class InsurancePolicyBridgeTests
 {
     [Test]
     public void ShouldIssueHealthPolicyWithProviderA()